Mersen OT65 250V K5 Fuse 65 Amp

Product Description

The MERSEN OT65 is a 250-volt, K5 class time-delay fuse rated for 65 amps. Class K5 fuses are dual-element, time-delay devices designed to carry temporary overloads — such as motor inrush current — without nuisance opening, while still providing fast response to sustained short-circuit faults. The OT65 fits standard fuse blocks and disconnects sized for 250-volt, 65-amp service. Licensed electricians and industrial maintenance technicians install this fuse in motor branch circuits, HVAC equipment, and general electrical distribution panels where K5 time-delay protection is specified.

The OT65 is appropriate for residential and light commercial HVAC systems, pump motors, compressors, and other motor-load branch circuits operating at or below 250 volts AC. It is commonly installed in safety switches and fusible disconnects during new construction or service replacement work. Always verify that the ampere rating and voltage rating match the equipment nameplate and the overcurrent protection requirements of the installation before installing.

Key Features

• 65-amp continuous current rating for medium-duty motor and equipment circuits
• 250-volt AC maximum voltage rating
• Class K5 dual-element, time-delay design tolerates motor inrush without nuisance tripping
• Fast response to short-circuit faults protects downstream equipment and wiring
• Fits standard fuse blocks and fusible disconnect switches rated for K5 class fuses

Compatibility

Designed as an OEM-style replacement or serviceable spare for branch-circuit fuse holders and fusible disconnects rated for 250-volt, 65-amp Class K5 fuses.

Installation Notes

Installation must be performed by a qualified electrician in accordance with the National Electrical Code (NEC) and all applicable local codes. De-energize and lock out the circuit at the upstream overcurrent device before removing or installing fuses. Confirm that the replacement fuse class, ampere rating, and voltage rating are consistent with the circuit design and equipment nameplate requirements. Do not substitute a higher-ampere or different-class fuse for the one specified by the equipment manufacturer.

Technical Specifications

• Ampere Rating: 65 amps
• Voltage Rating: 250 volts
• Fuse Class: K5
• Type: Time-Delay (Dual-Element)
• UPC: 78200170021

Standard Information

• Brand: MERSEN
• Manufacturer Part Number: OT65